Prior art modular building structures, specifically modular bathrooms such as that described in U.S. Pat. No. 8,596,021 to Van Ravenhorst, which is hereby incorporated by reference in its entirety, provide a flooring system referred to as the “Unifloor” system, and which is described as a composite construction (laminated fiberglass reinforced plastic) floor which can embody a simulated tile pattern, serves as the finished floor of the bathroom. In upscale environments such as high end commercial buildings and hotels, simulated finishes are not desirable.
U.S. Pat. No. 5,742,956 Tarver, which is hereby incorporated by reference in its entirety, teaches a modular bathroom unit floor fabricated of, for example, foam core material such as plywood sides having polystyrene foam or the like juxtaposed there between. Besides the well-known limitations of plywood as a moisture barrier, the moisture retention properties of plywood and resulting mold or mildew issues that can occur make plywood a less than desirable choice for flooring solutions in an environment that may be exposed to water. The use of plywood also results in increased weight to the bathroom module unit which increases shipping cost of the units.